(2600-2000+y)(12-4×y/25)=5000

问题描述:

(2600-2000+y)(12-4×y/25)=5000

(2600-2000+y)(12-4×y/25)=5000
(600+y)(12-4y/25)=5000
7200-96y+12y-4y^/25=5000
180000-2100y-4y^=125000
y^+525y-13750=0
(y-25)(y+550)=0
y=25或y=-550